To determine the role of the H-2 gene complex in modulating intercellular adhesion of normal embryonic fibroblasts obtained from congenic resistant mouse strains. To extend objective (1) to the effect of the H-2 system upon heterotypic tissue combinations, such as epithelial-fibroblast adhesion. To investigate factors that differentially affect cell-cell adhesion according to H-2 genotype. Such reagents as anti-H-2 isoantisera and neuraminidase appear to exert such a differential effect. To investigate the corticosteroid induced cleft palate model in which the H-2 genotype is linked to the incidence of cleft palate formation and to learn if developmental anomalies may be due to cell surface alterations that are reflected as changes in intercellular adhesion.